SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'af61357d6376070cb2324657c28043d3cf9ab3ab1e93988cb7f39c710a10d92e' 
  AND token = 'Ac0v8kuCpEZ6zdbkq3BCOwCBHsRtaqCvIygVqUYZ6xU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}